Vat dye.



STATES PATENT @FFTQE.

WILHELM BAUER, F VOHWINKEL, AND ALFRED HERRE AND RUDOLF MAY ER, 0FELBERFELD, GERMANY, ASSIGNORS TO FARBENFABRIKEN VCR-M. FRIEDR. BAYER &(10., OF ELBERFELD, GERMANY, A CORPORATION OF GERMANY.

Patented July 25, Elli.

VAT DYE.

998,596. Specification of Letters Patent. No Drawing.

To all whom it may concem:

Be it known that we, \VILHELM BAUER, residing at Vohwinkel, and ALFREDHanna and ll-uuom' MAYER, residing at Elberfeld,

Germany, doctors of philosophy, chemists,

citizens of the German Empire, have invented new and useful Improvementsin Vat Dye, of which the following is a specification.

Our invention relates to the manufacture and production of new andvaluable vat dyestuffs. They are obtained by condensing isatin compoundsin which the oxygen of the alpha-keto group is replaced by. easilymovable or replaceable substituents, e. g halogen, sulfur, the aminogroup, the alkoxy grolup with 4--oxyacenaphthcne of the formu a:

01 a, 0a2 l/\I/\ $11 The-new dyes are in a dry state dark blue Hg AH:

' Instead of the above isatin derivative other may be used, e. g.chloro-, brom0-,

Application filed September 13, 1910. Serial No. 581,795.

crystalline powders with a metallic luster which are soluble in hotnitrobenzene generally with a blue coloration, and which yield withhydrosulfite and caustic soda lye vats dyeing cotton after exposure toair grayish-blue to blue to green shades remarlc able for their fastnessto chlorin.

In order to illustrate the new process more fully we can proceed asfollows, the parts being by weight Example A: 305 parts of dibromoisatinare converted in a dry benzene suspension into dibromoisatin chlorid byheating it with 210 parts of P01 The mixture thus obtained is thenpoured into a hot solution which is well stirredof 175 parts of 4--oxyacenaphthene in dry benzene. The dye which separates on cooling isfiltered off and washed. It is a blue crystalline powder 45 soluble inhot benzene with a pure blue and in sulfuric acid with agreenish-bluecolor. Bytreatment with hydrosulfite and NaOHg a yellow vat results fromwhich cotton is dyed in fast pure blue shades. The formation of thecolor probably takes place according to the following formula:

and is soluble in hot nitrobenzene with a blue coloration and incoldconcentrated sulchlorobromoor dichloroisatin'chlorid,orthobromo-para-methylisatin chlorid, tI'lbIOIl'lOf isatinchlorid oaru-hronio-ortho-1nethylisw 2. The herein described newdyestufi 0b- 30 till enlorid, ortho-para-diniethynsetni ehlotmnaole fromdlhromoisatin-alpha-chlorid rid, ChlOlO- or bl'OZHO-bQZiL-fl *i'thisetlnchloand 4l-oxyacenaphthene, having the formula: ride suchdlhromo-hetumuphthlsetm chlo- Hi z P1-- --c0 00 TV 1 J i we einnn: i J3:) 1. The herein described new d3 teinehle irons. an compound v n. ofthe alpha-l eto 5. L 1 I/ placed y 21.11 easily znovahle or re'olesuhstltuent end koxyaeenu 40 the general formula: v hieh dyestuff is ina dry state a blue crysiii-lime powder, soluble in'hot benzene with npure blue and in concentrated sulfuric acid with a greenish-bluecoloration, and which yields with hydrosulfite and caustic soda lye 45it yellow vat from which cotton is dyed a pure blue, sul'istuntinlly asdescribed.

In testimony whereof We have hereunto set our hands in the presence oftwo subscribing Witnesses.

roben WILHELM BAUER. [LBJ t1 a blue coloration, and ALFRED HERRE. [n.s]

zene generally W1 wiiich yield with ydrosulfite and caustic RUDOLFMAYER. [11. s] soda lye vs cotton utter exposr v to sir i ue to h ue togree shat es iditnesses:

CHAS. J. XVILIGHT, ALFRED HENKEL.

